Track installation indicating system



- Filed Aug. 6, 1957 I INVENTOR [12; lien 0Z0 United States Patent TRACKINSTALLATION INDICATING SYSTEM Fritz Liewald, Berlin-Mahlsdorf, Germany,assignor to VEB Werk fiir Signalund Sicherungstechnik Berlin,Berlin-Treptow, Germany Filed Aug. 6, 1957, Ser. No. 676,582

Claims priority, application Germany Aug. 6, 1956 5 Claims. (Cl. 315-9)The present invention relates to a track diagram arrangement for therepresentation of the instantaneous operating conditions on tracks intrack boards, desks, etc.

It is customary to form track diagrams for diagrammatic control boardsby means of track diagram elements which abut each other without any gaptherebetween. The illumination of such diagrams is accomplished indifferent ways, for instance, by flood lighting, by light projections,etc., but always using for this purpose, incandescent lamps. The removalof the heat from the lamps is necessary in all cases, for the heat has adetrimental effect on the shape and size of the track diagram elementsand thus on the other structural parts of the track diagram table. Inaddition to the above mentioned defects, the shape and number of symbolswhich can be represented are limited. The prior systems also require alarge number of structural parts, some of which are difiicult tomanufacture. Among the above mentioned defects, one may particularlynote the still persisting problem of inadequate removal of the largeamount of accumulated heat and the detrimental result thereof, such asthe deformation and jamming of the structural elements of the system.

It is an object of the invention to provide a substantially simplifiedtrack diagram indicating arrangement.

Another general object of the invention is to avoid the above mentioneddefects of the prior art. This re sult is achieved in accordance withthe invention by the indication of the instantaneous operatingconditions of the track system, including the tracks, switches, signals,etc., using one or more cathode ray tubes preferably having a squareglass fluorescent screen. The deflecting voltages of the tubes arecontrolled by switches which are dependent on the train and/orinterlocking installations by applying voltages of diflerent wave formsand values one after another and/or simultaneously so as to formpredetermined indications or symbols on the fluorescent screens.

It will be evident that the system according to the invention has theadvantage, first of all, that there is no great production of heat invery small spaces and thus, structural means for the removal of the heatare not needed.

Another advantage of the present system is that structural parts ofcomplex construction are not needed for the deflection and guiding ofthe light, and the previously customary track diagram elementsthemselves and the structural supports therefor are not required.Another advantage over the prior systems is, that the quality of theillumination is increased since direct illumination is used.Furthermore, in view of the known multiple possibilities ofrepresentation of curves and symbols by cathode ray tubes, the shape andnumber of the symbols to be reproduced can be increased and made morelogical without substantially any additional technical provisions.

It will be evident that with the present system it is possible toprovide a continuous indication of train movement by presently knownmeans, such as changes in in- Patented Jan. 10, 1961 ductance in thetrack circuit. By the use of cathode ray tubes, the size of the trackdiagram is for the first time made independent of the size of theindividual structural parts such as the lamps, sockets, etc. and onlythe ease of viewing as a function of the position of the observer aredeterminative of the size of the track diagram and therefore, of thescreens of the cathode ray tubes.

The invention will be described in detail hereinafter in connection withthe drawings in which the figure is a diagrammatical representation ofone embodiment of the invention.

Referring to the drawings, the track diagram is formed by a plurality ofcathode ray tubes KR having preferably square screens contiguous withone another as indicated by S --S Over these screens there is placed amask G1 having a cut-out portion 11 corresponding to the tracks. Thescreens are preferably flat and in abutment with the mask. The mask andtubes may be suitably mounted and arranged to form a display board,table or desk. A plurality of operating keys of known type (not shown)may be arranged alongside of the cathode ray tubes in the usual manner.It is seen that the track diagram is divided among the several cathoderay tube screens. It will be understood that only a few of the cathoderay tubes are indicated and that in practice the mask or stencil G1 mayhave a track layout 11 extending over a very large number of cathode raytubes.

Each cathode ray tube is provided with a cathode 13, control grid 14, ananode 15 and a deflection system 16 The constant voltages for thecathode ray tube electrodes are supplied by a high voltage circuit 20which is energized by an alternating current supply circuit N. The gridvoltage is preferably made variable by means of a variable resistor orpotentiometer 21. Suitable control voltages, which may be sawtooth orsinusoidal voltages U U are fed to the vertical and horizontaldeflecting plates 17 and 18 through capacitors C and C Another controlvoltage U; is fed to control grid 14 through capacitor C The controlvoltages are fed to the cathode ray tube electrode through contacts a b,c, d. These contacts may be the usual contacts placed along railroadtracks and operated in accordance with various conditions occurringalong the tracks dependent on a train or interlocking installation. Inorder for instance to show a dotted line on the cathode ray tube screensa square voltage U; is app-lied to grid 14. The frequency of voltage Uapplied to deflection plate 18 for horizontal deflection is then madesufliciently high so that a solid line is preceived by the eye. It willbe understood that each of the other cathode ray tubes is similarlyoperated by control voltages applied to their electrodes through controlcontacts a, b, c and d adapted to be opened and closed as is well knownin accordance with the various conditions along the tracks. The contactsassociated with the various tubes may be arranged so as to applyvoltages thereto successively and/or simultaneously.

A signal may be indicated on the fluorescent screen with three dliferentmeanings. The three different color indications may be provided by meansof cathode ray tubes generally similar in construction to the tubes CR,but having tri-color screens. As is known from color television, upon acorresponding deflection of the cathode ray, the individual areas of thescreen may be caused to fluoresce in any one of these three differentcolors. One or more of the tubes may be formed to provide particularcolored signals in response to deflection voltages selectively appliedin the manner described above. For this purpose, the screen may bearranged to provide signals of three different colors, for example,green, red and yellow as indicated on screen S.

Small track diagrams utilizing only a few symbols can advantageously beformed with a single large cathode ray tube having a plurality ofdeflection systems for a like plurality of electron beams. In such anarrangement, the screen G1 may be masked in the same manner as thatillustrated in the drawings.

By the use of very small cathode ray tubes with screen sizes of 20 x 20mm, central control boards and track diagrams for central supervisioncan be made according to the invention in considerably smaller sizesthan has been previously customary.

The representation of operating conditions according to the invention isnot limited merely to use for track diagrams but can be used analgouslyfor visual boards in other pertinent fields, such as for instance, beltconveyor installations.

Although I have shown and described my invention in connection with oneembodiment thereof, it will be evident to those skilled in the art thatmany variations and modifications within the spirit and scope of myinvention may be made, and accordingly the invention is limited exceptas defined in the following claims.

I claim:

1. An arrangement for representing a railroad track installation andtrain movements and operating conditions along the track, comprisingcathode ray tube means including a plurality of cathode ray tubesarranged in juxtaposed horizontal and vertical rows having contiguousscreens constituting a flat extended fluorescent screen surface andmeans for projecting a plurality of electron beams onto separateadjacent portions of said fluorescent screen surface, said cathode raytube means further including deflection means and a control grid foreach electron beam; means for representing a single extended tracklayout on said surface including cover means for masking substantiallyall of said fluorescent surface except the portions representing thetrack, a plurality of sources of voltage of different wave forms andamplitudes; and switching means including train responsive switchesdisposed along the track for selectively connecting'said voltage sourcesto said deflection means and control grids of the several cathode raytubes in response to predetermined operational conditions along saidtrack for modulating the electron beams and deflecting them along saidtrack representing portions.

2. An arrangement according to claim 1, wherein said cathode ray tubeshave rectangular fluorescent screens forming said flat extended surface.

3. An arrangement according to claim 1, including cathode ray tube meansfor selectively producing a plurality of signals of different colors inresponse to different operational conditions along said track.

4. An arrangement for representing a system of vehicle tracks andindicating the positions of vehicles and other operating conditionsalong the tracks, comprising cathode ray tube means having atwo-dimensional array of contiguous fluorescent screen portions forminga flat extended fluorescent screen surface and means for projecting aplurality of electron beams individually onto said contiguous portionsof said fluorescent screen surface, individual control means for eachbeam in said tube means, said control means including a control grid andmeans for deflecting each electron beam in mutually orthogonaldirections, masking means covering substantially all of said fluorescentsurface except the portions representing the tracks for forming a singleextended track layout upon said extended screen surface, a plurality ofsources of voltages of different wave forms and amplitudes, a pluralityof switching means positioned along said tracks for response to thepassage of vehicles and to other operating conditions of the tracksystem, each of said switching means being electrically connectedbetween one of said voltage sources and the one of said control meanscontrolling that beam which impinges upon the portion of screen surfacecorresponding to the switch means position on the single extended tracklayout, for selectively connecting said voltage sources to said controlmeans for modulating the individual electron beams and deflecting themalong said track representing portions of the fluorescent screen surfacein response to the actuation of the voltage sources by the vehicles andother operational conditions along said track system.

5. An arrangement according to claim 4, wherein said cathode ray tubemeans includes means for selectively producing a plurality of signals ofdifferent colors in response to different operational conditions alongsaid track system.

Great Britain Feb. 6,

